The present invention relates to the general field of turbine engines. The invention relates more particularly to a system for deicing a splitter nose and inlet guide vanes of the primary passage through the turbine engine.
In an aviation turbine engine of the two-spool bypass type, the primary and secondary streams are split into respective flow passages downstream from the fan by means of a splitter nose. Within the primary passage, at the inlet to the low-pressure compressor (also commonly referred to as a “booster”), there is to be found a set of inlet guide vanes (IGVs).
During certain stages of flight, and also on the ground, the engines may encounter icing atmospheric conditions, in particular when ambient temperature is low enough and when humidity is high. Under such conditions, ice can form on the splitter nose and on the inlet guide vanes. When this phenomenon occurs, it can lead to the primary passage becoming partially or totally obstructed, and to blocks of ice breaking off and being ingested in the primary passage. An obstruction of the primary passage leads to the combustion chamber being fed with insufficient air, which chamber may then flame out, or the engine may be prevented from accelerating. In the event of blocks of ice breaking off, they can damage the compressor situated downstream and they can also lead to the combustion chamber flaming out.
In order to avoid ice forming on the splitter nose, known techniques include bleeding off hot air from a compressor in the primary passage, and injecting that hot air into the inside of the splitter nose. Thereafter, the hot air injected into the splitter nose can run along an inside wall of the nose until it reaches holes or grooves configured to inject the hot air into the primary passage towards the vanes for deicing. Using holes in the inner shroud carrying the guide vanes enables jets of hot air to be formed that can deice the inlet guide vanes, in part. Nevertheless, the holes or grooves in those devices cannot be located far enough upstream from the inlet guide vanes, which leaves little room for the jets to penetrate deeply into the primary passage so as to deice the vanes over a height that is sufficient.
Finally, the flow rate of hot air necessary for deicing the splitter nose and for ensuring that the jets of hot air for deicing the vanes can combat the stream of cold air entering into the primary passage is itself large. Bleeding off hot air in this way can reduce the performance and the operability of the turbine engine. It would therefore be desirable to be able to increase the effectiveness with which the nose and the inlet guide vanes are deiced without that simultaneously increasing the amount of hot air bled off from the compressor.